Technical Field
The present invention relates to an external storage device with a high tamper-proof property and a method of manufacturing an external storage device.
Related Art
In the business of making money by selling content, an external storage device in which the content is stored, for example, a memory card may be sold. In such a business model, the content stored in an external storage device is increasingly read by a dedicated device in recent years. When the external storage device is formed by a typical memory card, the information is transmitted to the dedicated device using a contact type external terminal (for example, see publication NO. 2002-083894 discloses performing non-type transmission of the information to the outside by providing an antenna coil in a semiconductor chip.
In the business of making money by selling content, it is important to suppress illegal duplication of the content, that is, to improve the tamper-proof property. A general method for improving the tamper-proof property depends on software processing, such as encryption of the content. However, even if the tamper-proof property is ensured by software processing, it becomes possible to read the contents if software which lowers the tamper-proof property, such as decryption software, is created. Thus, it has been difficult to sufficiently ensure the tamper-proof property.